I blame Congress for not updating SNAP to reflect nutritional common sense — and the terrible epidemics of obesity, hypertension and diabetes, which disproportionately affect low-income Americans but increase the entire country’s health-care bill.

The Physicians Committee for Responsible Medicine, a D.C.-based nonprofit, has proposed limiting SNAP purchases to whole grains; fresh, frozen or low-sodium canned vegetables; beans; and fruits. This meal plan would supply 65 percent less fat than the average American diet and twice the fiber, according to the committee. …

The counterargument is that it’s not fair to restrict poor people’s grocery choices. You hear this a lot from the food and beverage industry, for which SNAP has grown into a significant subsidy.

Sorry, I don’t get it — morally or pragmatically. Of course the federal government should be able to leverage its purchasing power for socially beneficial purposes. If you take Uncle Sam’s help, you play by his rules. I repeat: This is a nutrition program, or so the taxpayers who fund it are told. It should nourish.